• The Journal of the Petrological Society of Korea
• /
• v.5 no.1
• /
• pp.84-88
• /
• 1996

Pb isotope composition is analyzed from the rock chips of marbles intercalated between gneisses of Muju area and it shows very large variation ($^{206}Pb/^{204}Pb$=23.74~4142, $^{207}Pb/^{204}Pb$=16.32~18.43, $^{208}Pb/^{204}Pb$=36.42~39.75). The data points form well defined positive relationship on $^{206}Pb/^{204}Pb$ vs $^{207}Pb/^{204}Pb$ plot, which corresponds to $1.99{\pm}0.10$($2{\sigma}$) Ga. This age is very similar to the formation ages of the granitic gneisses from Buncheon and Cheondongri (Tanyang), and suggests that the fairly large volume of Sobaeksan Massif suffered regional metamorphism at this time. It is suggested that the most parts of Korean peninsula including Kyeonggi and Sobaeksan Massifs were very close each other and experienced a regional metamorphism together about 2.0 Ga ago from the fact that galenas from whole Korean Peninsula except Kyeongsang Basin and metamorphic rocks from Kyeonggi Massif also reveal a similar slope corresponding 2.0 Ga on Pb-Pb isotope plot.

• Journal of Preventive Medicine and Public Health
• /
• v.21 no.2 s.24
• /
• pp.271-283
• /
• 1988

A Fourier transform infrared spectrophotometric method was described for the determination of quartz, mica(sericite) and feldspar(potassium feldspar) in respirable dust in Taebaek area. The results were as follows; 1) The concentration of minerals were determined from the intensity of absorption peak of quartz at $799cm^{-1}$, sericite at $539cm^{-1}$, and potassium feldspar at $648cm^{-1}$ respectively. 2) The precision(C. V. %) for the quartz determination was $7.70{\pm}2.68%$ from 10 to $200{\mu}g$ of quartz. 3) The precision for the sericite determination was $16.34{\pm}6.82%$ from 30 to $500{\mu}g$ of serictite. 4) The precision for the potassium feldspar determination was $5.28{\pm}1.74%$ from 30 to $500{\mu}g$ of potassium feldspar. 5) The concentration of respirable dust in Taebaek area was $4.90{\pm}3.29mg/m^3$ (0.4-93.7%), percent quartz was $1.80{\pm}4.14%$ (0.01-20.56%), percent sericite was $11.37{\pm}6.43%$ (0.00-29.69%), percent potassium feldspar was 8.15% (n=7, 3.41-19.70%). 6) The difference of respirable coal dust, quartz, and sericite concentrations in drilling, coal cutting, hauling and seperating was significant respectively (p<0.05).

• Journal of the Korean Wood Science and Technology
• /
• v.46 no.5
• /
• pp.437-448
• /
• 2018

Physical characteristics of Korean red pine (Pinus densiflora) were investigated with different cultivation locations in Taebaek Mountains as Goseong-gun, Hongcheon-gun and Bonghwa-gun as experimental sites. Moisture content based on air-dried or green (artificial) wood was no significant differences with different cultivation places. Specific gravities of both sapwood and heartwood of red pine from Bonghwa-gun were higher than those from other two sites (Hongcheon-gun or Goseong-gun). Specific gravity of heartwood of red pine from Goseong-gun was higher than it from Hongcheon-gun, but this trend was opposite in case of sapwood. Higher specific gravity of red pine heartwood from Goseong-gun maybe resulted in higher strength than those of other sites. In shrinkage ratio, there was no significant difference among different cultivation places in radial directions, but red pine from Bonghwa-gun was higher than those of other sites in tangential directions. Hygroscopicity was no significant differences with different cultivation places. These results will be helpful information for efficient use of pinewood and good quality of pinewood production for genetical breeding improved.

• Journal of the Korean GEO-environmental Society
• /
• v.4 no.2
• /
• pp.15-25
• /
• 2003

Time Domain Refletometry, or TDR, is a remote sensing electrical measurement technique that has been used for many years to determine the spatial location and nature of various objects, especially in the United States of America and Australia at mining industry. Since early on 1990, the TDR techniques have been applied to the geotechnical engineering such as : deformation measurement of rock slope and landslide, monitoring of ground water content and ground water level change, investigation of ground contamination and its movement. The first application of this technique, in 1996, to the domestic area is to determine the possibility of ground settlement caused by subsidence from abandoned underground mines at the Tongri and Gosari in Gangwon-d. In this paper, through the results of analysed deformation data between conventional measurements and the TDR, it was concluded that the TDR technique is a useful instrumentation method for the prediction of ground deformation.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.37 no.6
• /
• pp.827-832
• /
• 2013

In this study, curve responsiveness was assessed based on the lateral force and running safety was evaluated based on the wheel unloading ratio and derailment coefficient, which is the ratio of the wheel load and the lateral force. The evaluation of the curving performance and running safety of the new high-power electric locomotive showed that the derailment coefficient appeared higher when the wheel-set was set to the front of the train instead of being placed backward, and the maximum value of the derailment coefficient was recorded as 0.572 on the Gyeongbu line. Furthermore, the lateral force increased in curved sections, and it appeared to be proportional to the curve radius. Meanwhile, a maximum axis lateral force of 77.6 kN was recorded on the Taebaek line, and the wheel unloading ratio was 47.6% on the Yeongdong line. Finally, the running safety at the maximum speed as well as the through-curve performance of the curve radius satisfied the required standards.

• Journal of the Korean Society of Hazard Mitigation
• /
• v.7 no.2 s.25
• /
• pp.53-63
• /
• 2007

This study is to evaluate the probable snowfall depth by the point frequency analysis and to draw the map of probable snowfall depth in Korea. The 14 probability distributions which has been widely used in hydrologic frequency analysis are applied to the annual maximum depth of snowfall data. The parameters of each probability distribution are estimated by method of moments, maximum likelihood method and method of probability weighted moments. The estimated parameters were checked by parameter validity conditions of each assumed probability distribution. Four tests that are $X^2-test$, Kolmogorov-Smirnov test, Cramer von Mises test and probability plot correlation coefficient test are used in this study to determine the goodness of fit of the distributions. Mostly the 2-parameter gamma distribution was determined as appropriate distribution for the annual maximum new snowfall depth. The probable snowfall depth were obtained from appropriate distribution for the selected return periods and the maps of probable snowfall depth were presented. It will be useful to specify the snowfall load for the design of agricultural facilities such as vinyl house and cattle shed.

• Economic and Environmental Geology
• /
• v.38 no.3 s.172
• /
• pp.299-304
• /
• 2005

Geoid undulation and gravity anomaly were calculated from GRACE satellite data on the eastern Asia including Korean peninsula. Geoid undulation varies from -60m in the China to 60m toward the Pacific Ocean across the Korean Peninsula. Calculated gravity anomalies are in the range of -60 and 60 mgal except the subduction zone showing -100 mgal. High positive values are observed at Mt. Baekdu, Kaema highland and Taebaek mountains, and low values at Ulleung, Japan and Yamato basins in the East sea. We removed regional components below the spherical harmonic degree of 10 from gravity anomaly to get the residual anomaly for crust components. Residual gravity anomaly shows high anomalies at the northern mountainous area and Kyungsang basin in the Korean Peninsula. And low anomalies appears at the western Korea bay basin, Kunsan basin, Cheju basin, and Ulleung basin in the marine. Anomalies separated by the spherical harmonic degree as well as the residual anomalies are useful for the study of large crustal structure about geologic scale and depth distribution and for the survey of natural resources.

• The Journal of Engineering Geology
• /
• v.20 no.1
• /
• pp.71-78
• /
• 2010

The Gagok mine is a contact metasomatic deposit, located at Gagok-myeon, Samcheok city and Cheoram-dong, Taebaek city, Gangwon province. The deposit lies within the limestone of Myobong and Pungchon formations, and exists the contact of intrusive granite porphyry. In order to determine the direction and extension of mineralization in the gallery and around the entrance of the ore deposit, we used the ground magnetic survey, the direct current (dc) resistivity survey using dipole-dipole array, and resistivity tomography survey. The ground magnetic survey did not detect the anomalous zone due to ore deposit, while the dc resistivity survey and resistivity tomography survey were successful in delineating the anomalous zone related to the extension of fault toward $N50^{\circ}W$.

• Tunnel and Underground Space
• /
• v.11 no.1
• /
• pp.64-71
• /
• 2001

The purpose of this study is to develop rail rockfall and landslide information system to manage spatial database using GIS. For this, a spatial database containing information such as railroad, map, topographic analysis, meteorological data, and rockfall has been constructed for 2.5 km or 5 km buffer zone from the Kyungchun, Youngdong, Jungang, Taebak and Jungsun Rairoad where risk of landslide occurrence potential is high. For management of the spatial database, railroad rockfall and landslide information system has been developed. The information system consists of view, table, chart, layout and project environment. The functions provided in the system are data conversion, editing, labeling, zoom in and out, map making, graphic editing, text DB management, charting, on-line help as well as input, retrieve and output of spatial database. The system was developed using ArcView script language Avenue, and consisted of pull-down menus and icons for easy use. The spatial database and the information system can be used to rockfall and landslide management and analysis near the railroad as basic data and tool.

• Economic and Environmental Geology
• /
• v.18 no.3
• /
• pp.247-251
• /
• 1985

The sulfide and carbonate mineral samples for sulfur and carbon isotope studies were collected from Sangdong, Geodo, Yeonhwa, Shinyemi and Janggun mines which are distributed in the Metallogenetic Province of the Taebaeg Mt. Region. The ${\delta}S^{34}$ values of molybdenite, pyrite, arsenopyrite, pyrrhotite, chalcopyrite, sphalerite and galena from the above mines are similar and within the range of +1.66 to +6.77‰ with the exception of chalcopyrite from Geodo mine ranging from -1.58 to 1.96‰, while the sulfide minerals are dominated by positive values between +3.05 and +5.08‰. It is suggested that the major sulfur source is genetically related to the Cretaceous granitic activity. The average ${\delta}C^{13}$ values of calcite from limestone, calcite from calcite vein in ore bodies and granite, and rhodochrosite from ore bodies are -0.60‰, -2.69‰ and -6.00‰, respectively. The data on carbon isotope compositions indicate that the calcite from limestone originated in marine environment, the rhodochrosite in hydrothermal solution, and calcite from calcite vein and granite in the mixing condition of marine and hydrothermal waters. The temperatures of mineralization by the sulfur isotopic composition coexisting pyrite-pyrrhotite from Yeonhwa No.1, sphalerite-galena from Weolam and Dong-jeom of Yeonhwa No.1 mine, sphalerite-galena and pyrite-galena from Janggun mine were $273^{\circ}C$, $460{\sim}511^{\circ}C$, $561{\sim}690^{\circ}C$, $341^{\circ}C$ and $375^{\circ}C$, respectively.